Effluent cleaner for trash-burning

ABSTRACT

Located adjacent to a trash-burning building, such as a building in which flammable material is burned from automobiles, effluent cleaning apparatus includes a secondary furnace for burning combustible gases and a tortuous horizontal flue, a water pit in a reversing flow path for collecting particles, washing sprays within the water pit and within a discharge stack, and a mechanical filter in the discharge stack.

[ July 17, 1973 110/8 Mercer................,,......... llO/l19 X 3,520,113 7/1970 Stokes 2,592,491 4/1952 Toepel 3,572,264 3/1971 1 1 EFFLUENT CLEANER FOR TRASH-BURNING [76] Inventor:

William R. Allbritton, 257 Old Mill Lane, Dallas, Tex. 75217 Nov. 10, 1971 Primary Examiner-Kenneth W. Sprague Attorney-Cecil L. Wood and Peter J. Murphy [22] Filed:

[57] ABSTRACT Located adjacent to a trash-burning building, such as a building in which flammable material is burned from automobiles, effluent cleaning apparatus includes a Appl. No.: 197,351

[58] Field of Search................'..,. 110/8 R, 8 A, 8 C, secondary furnace for burning combustible gases and 110/119 a tortuous horizontal flue, a water pit in a reversing flow path for collecting particles, washing sprays within the water pit and within a discharge stack, and a mechanical filter in the discharge stack.

S T N m M e mm mT .RS 8

D RE n N U N U 110/8 9 Clainis, 5 Drawing Figures 3,310,009 3/1967 Jacobs PATENIEDJUL 1 ms SHEET 1 BF 2 Fig.5

INVENTOR. W||l|0m R. Allbrif'ron Fig.3

ATTORNEY PAIENIEUJHWW SHEET 2 0f 2 IN VENTOR.

3 iIIIIIZI William R. Allbriflon ATTORNEY BACKGROUND AND SUMMARY OF THE INVENTION This invention relates to improvements in cleaners for effluent; and more particularly to apparatus for removing pollutant materials from effluent such as smoke from waste burners and incinerators.

Recent years have witnessed an ever increasing need for the reduction, and eventual elimination, of pollutants from mans environment. Heretofore, many attempts have been made to separate unwanted materials from the normal gaseous products of combustion from installations for the burning of trash. These efforts have yielded only a moderate degree of success, and altogether too frequently the effluent discharged to the atmosphere still retains large amounts of undesirable material.

An object of this invention is to provide effluent cleaning apparatus which pennits the burning in an enclosure of products normally providing a dense smoke discharge, but which discharges no undesirable smoke to the atmosphere.

A more particular object of this invention is to provide effluent cleaning apparatus for use with a building in which trash such as automobiles are burned at which time the automobile tires, cushions and the like are all burned which notoriously produce a large volume of smoke, but the smoke produced thereby is cleansed by the apparatus of the invention. I

Another object of this invention is to provide an apparatus for use with a trash-burning building which is capable of removing substantially all of the undesirable pollutants from the flue gases.

A further object of this invention is to provide effluent cleaning apparatus for use with a trash-burning building which is relatively compact, efficient andxeconomical with respect to original cost and operation and maintenance.

For accomplishing theseobjects, apparatusaccording to the invention comprises a secondary. furnace havingflame producing means at its inlet end for buming gaseous combustibles in the effluent and a horizontally disposed tortuous path leading to the outlet end to permit the settling of heavier particles. A water pit is provided with a diving flue inlet and an outletdefined by a discharge stack whereby the flow of effluent through the water pit is reversed affecting further re moval of heavier particles. Spray nozzles on the stack wet smaller particles which are retumedto the water pit, and the effluent is filtered prior to discharge from the stack.

The novel features of the invention, as well as additional objects and the advantages thereof, will be understood more fully from the following description when read in connection with the accompanying drawmgs.

DRAWINGS FIG. 1 is a perspective view of a trash-burning building and associated effluent cleaning and discharge apparatus according to the invention.

FIG. 2 is a sectional view of the components of the effluent cleaning apparatus and of a portion of the trash-burning building taken in vertical planes, as indicated by the line 22 of FIG. 1.

FIG. 3 is a horizontal sectional view of the secondary furnace as viewed along the line 3--3 of FIG. 2.

FIG. 4 is a transverse sectional view through the lower portion of the stack, viewed along the line 4-4 of FIG. 2, showing the water spray nozzles and associated equipment, and

FIG. 5 is a transverse sectional view through the upper portion of the stack, viewed along the line 5--5 of FIG. 4, showing the filter apparatus and vent cap.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring particularly to FIGS. 1 and 2 of the drawing, a trash-burning building 10 is illustrated as being generally rectangular including side walls 11, end walls 12 and roof panels 13, which converge to form an apex or peak 14. The building illustrated is suitable for burning trash such as old automobiles for the purpose of eliminating all burnable materials from the automobiles prior to their use as scrap metal. Such bumables nor mally include upholstery, tires, cushions, various rubber installations, grease and the like, all of which produce heavy smoke. The building side walls 11 are provided with a plurality of doors 15 through which the trash is deposited in and removed from the building furnaces by means of suitable conveyances or conveyors for example.

Inlet fans 16 are mounted in one or both end walls 12 for providing air for combustion within the building enclosure and also for assisting in afiecting the flow of effluent from the apex portion 14 of the building through an outlet duct 17, the upper end of which is secured in an opening in one end wall 12 near the apex of the roof, and which extends downwardly on the exterior of the building to the effluent cleaning apparatus to be described.

In. general, the effluent cleaning apparatus includes a secondary furnace 20, a water-pit 21, and a stack 22 from which the effluent is discharged to the atmosphere. These components and the associated apparatus will now be described in detail.

In relation to the flow stream of the effluent from the building 10, the firstcomponentof the effluent cleaning apparatus or system is the secondary furnace 20 which is a rectangular structure fabricated of suitable brick for example, andconstnicted on a concrete base or platform 25 which also functions as the, platform for other components of the system. The furnace 20 is a closed rectangularstructure including end walls 26 and 27 and side walls 28 and 29 and having a generally flat roofstructure 30. The end wall 26 defines the inlet end of the furnace 20, the outlet duct 17 of the building I0 being connected to a suitable opening in the inlet wall 26.

Internally of the housing, a vertical central partition 33, spaced from and parallel to the inlet wall 26,.defines with the inlet wall a combustion chamber 34 within which is placed a gas burner 35 having a fuel line 36. The efi'luent from the duct 17 passes into the combustion chamber 34 and any combustible solids or gases within the effluent are consumed within the combustion chamber. The ends of the central partition 35 terminate short of the side walls 28 and 29 defining therewith vertical openings through which the effluent flows from the combustion chamber.

A similar central vertical partition 37 is provided and spaced from and parallel to the outlet wall 27 defining similar vertical passages at the ends thereof. Between the central partitions 33 and 37 are provided vertical partitions 38 and 39 which extend inwardly from the respective side walls 28 and 29 parallel to the partitions 33 and 37. The partitions 38 and 39 also extend from the floor to the roof structure, but define a central vertical opening for the flow of effluent. The partitions 33, 37, 38 and 39 then define tortuous horizontal paths for the flow of effluent from the combustion chamber 34 to the effluent outlet in the outlet wall 27.

As best seen in FIG. 2 of the drawing, the water pit 21 is disposed adjacent to the furnace and beneath the concrete platform 25. The water pit may be fabricated as a metallic tank 42 set in the ground beneath the platform, for example, or may be of any other suitable construction. With the water pit positoned adjacent to the furnace 20, the effluent flows therefrom through a diving flue 43 which directs the effluent downwardly from the secondary furnace outlet into the water pit. The level of water 44 is maintained at an appropriate level by means of a float operated valve 45 supplied from a suitable supply conduit 46. The water is maintained at a level to provide a chamber at the upper portion of the pit for the flow of effluent.

The stack 22 is supported on the platform directly above the water pit, so that the effluent flows vertically upward from the water pit through the stack to be discharged to the atmosphere. The stack 22 may be fabricated of metal, for example, and may be supported on the platform 25 by means of suitable legs or braces 50. A suitable vent cap 51 is provided at the upper end of the stack.

A plurality of horizontally disposed confronting spray nozzles 54 and 55 are mounted in the walls of the stack 22, adjacent to the lower end thereof, for washing the effluent as it flows upwardly from the water pit 21 through the stack. These spray nozzles are supplied by a suitable water pump 56 through pipes 57, the water being supplied to the pump from the water pit 21 through a suction pipe 58. The pipe 57 also supplies water to downwardly directed spray nozzles 59 which are supported adjacent to the upper wall of the water pit 21 to wash the effluent flowing through the water pit from the diving flue 43 toward the stack 22.

Because of the reversal of the flow of the effluent from the downwardly directed diving flue 43 to the stack 22, some of the heavier non-combustible solid particles carried in the efi'luent will fall into the water 44 by gravity, while other particles will be carried to the water surface by momentum. Other lighter particles will be washed out of the effluent by the downwardly directed spray nozzles 59, and these wetted particles will of course be carried to the water in the pit. Additional solid particles which remain in the effluent as it starts its travel up the stack, will be wetted by the spray nozzles 54 and 55 and will be carried downwardly into the water pit by the water emanating from these nozzles.

In time, the solid particles collected in the water pit will form a sludge at the bottom of the tank 42, and this sludge is removed periodically by means of a suitable pump 61 mounted on the platform 25, having a suction conduit 62 extending to the bottom of the water pit and the discharge conduit 63. The pump may also be used, of course, for periodic draining of the water pit for the purpose of inspection or maintenance.

A filter 65 is provided adjacent to the upper end of the stack 22 to provide a final filtering of solid particles from the effluent. The filter shown in the drawings, by way of example, includes a fibrous filtering material 66 which completely occupies the cross-section of the stack, and which is confined between lower and upper screens 67 and 68 respectively.

The operation of the above-described efiluent cleaning apparatus and system will now be briefly summarized.

The flow of effluent through the system is accomplished partially by the draw of the elevated stack 22 and partially by a forced flow effect created by the introduction of air into the trash-burning building 10 by the inlet fans 16.

The effluent passing from the building 10 through the outlet duct 17 likely contains both combustible and non-combustible solid particles and combustible and non-combustible gases. Further combustion and consumption of the combustible solids and gases is effected in the combustion chamber 34 of the furnace 20. With the horizontal flow of the effluent from the combustion chamber through the tortuous path to the diving flue 43, some of the heavier solid particles will settle out by gravity, collecting on the floor of the furnace structure 20 for removal when sufficient accumulation has occurred.

The effluent then flows through the diving flue 43 to the water pit 21 where a reversal of flow direction occurs between the diving flue and the stack 22. There will be additional removal of the solid particles from the effluent both by gravity and by centrifugal force as the effluent changes direction in the water pit. As the effluent passes horizontally from the diving flue toward the stack, additional lighter particles will be wetted by the water spray from the nozzles 59 and will settle to the water surface. Additional wetting of the lighter particles in the efi'luent will occur as the effluent starts its flow upwardly from the water pit, this wetting being effected by the spray nozzles 54 and 55, and these wetted particles will be carried back to the water pit with the water emanating from these nozzles.

The final cleansing of the effluent occurs as the effluent flows through the filter 65, and from the succession of cleansing operations, the effluent exhausting from a stack to the atmosphere is substantially free of objectionable air pollutants.

Although the invention has been described with ref-- erence to a particular preferred embodiment, many changes-and modifications will become apparent to those skilled in the art in view of the foregoing description which is intended to be illustrative and not limiting of the invention defined in the claims.

What is claimed is:

1. For use with a trash-burning building defining a primary combustion chamber and including duct means for carrying gaseous effluent from the building, effluent cleaning apparatus comprising:

a secondary furnace comprising housing means having an inlet at one end, for communication with said duct means, and an outlet at the other end; said housing defining a combustion chamber at the inlet end, having disposed therein a flame producing burner, and means defining a laterally directed tortuous path from said combustion chamber to said furnace outlet;

means defining a water pit disposed adjacent to said secondary furnace; means maintaining the water level in said pit to define a lateral effluent path above the water; a diving flue communicating said furnace and said water pit, effluent path for directing effluent downwardly into said water pit;

vertical stack means supported above said water pit and communicating with said water pit effluent path for discharging the efiluent to the atmosphere; and a plurality of liquid spray nozzles disposed within said stack means for washing the effluent flowing from said water pit upwardly through said stack means.

2. Effluent cleaning apparatus as set forth in claim 1 wherein said tortuous path in said furnace housing is provided by a first central baffle defining one wall of said combustion chamber and flow paths adjacent to the side walls of the furnace housing, a pair of baffles located in spaced relation one adjacent to each side wall of the burner housing and defining a central flow passage, and a second central baffle defining flow passages adjacent to the housing side walls.

3. Effluent cleaning apparatus as set forth in claim 1 posed adjacent to each other opening to said water pit effluent path; said water pit defining a flow reversing chamber between said. diving flue and said stack means.

5. Effluent cleaning apparatus as set forth in claim 1 including downwardly directed water spray means in said water pit for washing the effluent flowing through said lateral flow path.

6. Effluent cleaning apparatus as set forth in claim 1 including filter means disposed adjacent to the upper end of said stack means for collecting suspended particles remaining in the effluent.

7. Effluent cleaning apparatus as set forth in claim 5 including fluid pump means having a suction inlet communicating with the water in said water pit, and having its outlet communicating with said nozzle means in said stack and in said water pit.

8. Effluent cleaning apparatus as set forth in claim 1 including fluid pump means having its suction inlet disposed adjacent to the bottom of said water pit for removing collected sludge from said water pit.

9. Effluent cleaning apparatus as set forth in claim 1 including fluid pump means having a suction inlet communicating with the water in said water pit, and having its outlet communicating with said nozzle means in said stack. 

1. For use with a trash-burning building defining a primary combustion chamber and including duct means for carrying gaseous effluent from the building, effluent cleaning apparatus comprising: a secondary furnace comprising housing means having an inlet at one end, for communication with said duct means, and an outlet at the other end; said housing defining a combustion chamber at the inlet end, having disposed therein a flame producing burner, and means defining a laterally directed tortuous path from said combustion chamber to said furnace outlet; means defining a water pit disposed adjacent to said secondary furnace; means maintaining the water level in said pit to define a lateral effluent path above the water; a diving flue communicating said furnace and said water pit, effluent path for directing effluent downwardly into said water pit; vertical stack means supported above said water pit and communicating with said water pit effluent path for discharging the effluent to the atmosphere; and a plurality of liquid spray nozzles disposed within said stack means for washing the effluent flowing from said water pit upwardly through said stack means.
 2. Effluent cleaning apparatus as set forth in claim 1 wherein said tortuous path in said furnace housing is provided by a first central baffle defining one wall of said combustion chamber and flow paths adjacent to the side walls of the furnace housing, a pair of baffles located in spaced relation one adjacent to each side wall of the burner housing and defining a central flow passage, and a second central baffle defining flow passages adjacent to the housing side walls.
 3. Effluent cleaning apparatus as set forth in claim 1 including a gas burner disposed in said combustion chamber.
 4. Effluent cleaning apparatus as set forth in claim 1 wherein said diving flue and said stack means are disposed adjacent to each other opening to said water pit effluent path; said water pit defining a flow reversing chamber between said diving flue and said stack means.
 5. Effluent cleaning apparatus as set forth in claim 1 including downwardly directed water spray means in said water pit for washing the effluent flowing through said lateral flow path.
 6. Effluent cleaning apparatus as set forth in claim 1 including filter means disposed adjacent to the upper end of said stack means for collecting suspended particles remaining in the effluent.
 7. Effluent cleaning apparatus as set forth in claim 5 including fluid pump means having a suction inlet coMmunicating with the water in said water pit, and having its outlet communicating with said nozzle means in said stack and in said water pit.
 8. Effluent cleaning apparatus as set forth in claim 1 including fluid pump means having its suction inlet disposed adjacent to the bottom of said water pit for removing collected sludge from said water pit.
 9. Effluent cleaning apparatus as set forth in claim 1 including fluid pump means having a suction inlet communicating with the water in said water pit, and having its outlet communicating with said nozzle means in said stack. 